Van Diesel
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- 99CR
My very good friend 'Bagman' passed me three of these Hantarex Switch-mode power supplies to repair last week, so I decided to delve into them.
I know for certain that one of these is from a 'Chase HQ' cabinet which needs fixing.
You're not going to easily replace these power supplies with other off-the-shelf models as they also provide 135V DC for the Hantarex MTC9000 Monitors being used with these games.
Let's see what we can find . . .
Quite an 'open' design in comparison to many modern units. One thing I noticed immediately was that the board has quite a 'flex' to it, and you need to bend it slightly to get it in and out of the metal shell. A possible future issue with broken tracks methinks, depending on what sort of life it has had.
I started with a visual inspection of all three units with the intention of repairing anything I saw that was dodgy before moving further on.
I feel fortunate in that fact that there was no great repair 'head scratching' needed for this job, and I was able to get all the units back into working order fairly swiftly.
First off . . . uh oh . . . this doesn't look right. One of the main rectifier diodes (BY255) looks like an alligator out of 'Jungle King' has taken a bite out of it or something.
Lifting it out off the board, the thing broke apart.
Ok, I don't think that's going to work again . . .
I checked the other diodes and one was a direct short - The other two were OK.
Bad Diodes replaced.
The 100K power resistor on the previous photo looked like it had seen 'some action' but measured to be fine and other than the discolouration, didn't seem a threat to anything so I left it alone.
You can't see it easily on the photo but there is a dry-joint there. One of the pins of the long power resistors - It's loose in it's hole!
Time to sort it out with a good jallop of the metal glue so it doesn't happen again.
Hey now, hey now, now . . . there's this corrosion! Sweet Sister's of Mercy!
Not sure what's happened here . . . maybe the ingress of some damp at some stage.
It needs a good clean up, the track reinforcing and some green UV solder paint applied to it.
This area of the board is very close to the 5V adjustment potentiometer . . . Hmmm . . .
Looks like 'this corrosion' has penetrated into our force field . . . or at least, the 100 ohm variable resistor. Strange, but on two of the three boards I am repairing . . . these little PCB mounted jobbies were faulty. One was completely open-circuit on all three pins, another open-circuit on one of them.
All were replaced with new ones. Fortunately, I managed to source 100 ohm potentiometers with the hex fitting, so I was able to reuse the original adjusters.
Incidentally, the symptoms of running the power supply with a bad control potentiometer was that the 5V rail was around 1V or less and could not be adjusted in any direction.
Cap'n she's gonne blow!
Christ on a pushbike, this main HT capacitor was bulging like a teenager looking at photos of Kim Kardashian!
All the capacitors on all the boards were in great condition (ESR checked) but this one's not going to cut the mustard. Time to be replaced.
Right, let's get them powered up!
I used a standard 60W filament bulb on the 135V DC side to check the monitor power, and some low voltage bulbs to test the 5V side at about 1 Amp current.
They're looking good! Adjusted the voltage for exactly 5.1V on the meter.
Job's a good-un . . . I didn't even need to get my 'scope out or anything. Sweet.
They've been running for over 30 years and with luck they'll run for 30 more!
I'd recommend getting fans on these units to be honest for reliability. If you think about it, low-cost PC supplies rated at 250W all have fans built in.
I believe the Hantarex US300's (next step up to these) have externally mounted fans.
With luck, my friend will have his Chase HQ cabinet back up and running again!
(God, I hate the sound from that game. The attract mode police siren sound used to drive me nuts back in the day!)
Toodle-pip
Van
Van Diesel2020-12-24 11:12:39
I know for certain that one of these is from a 'Chase HQ' cabinet which needs fixing.
You're not going to easily replace these power supplies with other off-the-shelf models as they also provide 135V DC for the Hantarex MTC9000 Monitors being used with these games.
Let's see what we can find . . .
Quite an 'open' design in comparison to many modern units. One thing I noticed immediately was that the board has quite a 'flex' to it, and you need to bend it slightly to get it in and out of the metal shell. A possible future issue with broken tracks methinks, depending on what sort of life it has had.
I started with a visual inspection of all three units with the intention of repairing anything I saw that was dodgy before moving further on.
I feel fortunate in that fact that there was no great repair 'head scratching' needed for this job, and I was able to get all the units back into working order fairly swiftly.
First off . . . uh oh . . . this doesn't look right. One of the main rectifier diodes (BY255) looks like an alligator out of 'Jungle King' has taken a bite out of it or something.
Lifting it out off the board, the thing broke apart.
Ok, I don't think that's going to work again . . .
I checked the other diodes and one was a direct short - The other two were OK.
Bad Diodes replaced.
The 100K power resistor on the previous photo looked like it had seen 'some action' but measured to be fine and other than the discolouration, didn't seem a threat to anything so I left it alone.
You can't see it easily on the photo but there is a dry-joint there. One of the pins of the long power resistors - It's loose in it's hole!
Time to sort it out with a good jallop of the metal glue so it doesn't happen again.
Hey now, hey now, now . . . there's this corrosion! Sweet Sister's of Mercy!
Not sure what's happened here . . . maybe the ingress of some damp at some stage.
It needs a good clean up, the track reinforcing and some green UV solder paint applied to it.
This area of the board is very close to the 5V adjustment potentiometer . . . Hmmm . . .
Looks like 'this corrosion' has penetrated into our force field . . . or at least, the 100 ohm variable resistor. Strange, but on two of the three boards I am repairing . . . these little PCB mounted jobbies were faulty. One was completely open-circuit on all three pins, another open-circuit on one of them.
All were replaced with new ones. Fortunately, I managed to source 100 ohm potentiometers with the hex fitting, so I was able to reuse the original adjusters.
Incidentally, the symptoms of running the power supply with a bad control potentiometer was that the 5V rail was around 1V or less and could not be adjusted in any direction.
Cap'n she's gonne blow!
Christ on a pushbike, this main HT capacitor was bulging like a teenager looking at photos of Kim Kardashian!
All the capacitors on all the boards were in great condition (ESR checked) but this one's not going to cut the mustard. Time to be replaced.
Right, let's get them powered up!
I used a standard 60W filament bulb on the 135V DC side to check the monitor power, and some low voltage bulbs to test the 5V side at about 1 Amp current.
They're looking good! Adjusted the voltage for exactly 5.1V on the meter.
Job's a good-un . . . I didn't even need to get my 'scope out or anything. Sweet.
They've been running for over 30 years and with luck they'll run for 30 more!
I'd recommend getting fans on these units to be honest for reliability. If you think about it, low-cost PC supplies rated at 250W all have fans built in.
I believe the Hantarex US300's (next step up to these) have externally mounted fans.
With luck, my friend will have his Chase HQ cabinet back up and running again!
(God, I hate the sound from that game. The attract mode police siren sound used to drive me nuts back in the day!)
Toodle-pip
Van
Van Diesel2020-12-24 11:12:39
